Parthian Ships 1928 +

Kaiser Kirk · December 06, 2024, 01:18:41 AM

Parthia has approached that differently. There's primarily has MTBs for that role, with ~700 currently in service, deployed largely into squadrons of 24 or 48. Hopefully enough to saturate the defenders , and enough torpedoes to get a fair number of hits, at a fairly low cost.

As for the older destroyers Parthia has followed the Byzantine lead with the 500-750t x 64 'torpedo boat leaders' but they are ageing, and lack the sustained high cruising speed, the ASW ability, and have less torpedoes. The older 1000tonners may be moved to that role, but they are also aging out.

The Sea Hornet style would be able to 'hide' in coastal shallows as a 'fleet in being', but still race out and interdict or attack weaker formations. And I could afford them in acceptable numbers.

edit : since the Pahlavi word for hornet is not in my Pahlavi-English dictionary pdf, I will call it the 'Yoz' or "Cheetah"

Kaiser Kirk · December 11, 2024, 11:55:41 PM

1936

Looking forward into 1936, Parthia has a oddity in the production schedule – not many new classes to design.

Part of that is Parthia tends to build classes for several years, which is practical and would have benefits of commonality and scale. But that means I repeat ships instead of having new designs each year.

The newest carrier was completed and is on trials, at the same time the 1938 aircraft are brand new in service. The first two armored carriers are completing. I think the Parthians would really want to see how these all work together before laying down more carriers. So none until 1937.

The new Destroyer Leader, Coastal Destroyer and Patrol Sloop III all are somewhat new TYPEs not just classes and are on trials with training squadrons, so they would want to wait until these new ships have worked up before committing to a full building program.

Looking at my ships, the oldest classes in production are the
1926 Motor Gunboat series I – a riverine/coastal gunboat with a 90mm gun and 118mm howitzer on 60tons.

1922 Deniz Ghoorbagheh – a light tender design to support small squadrons. I suppose I could update it.

Neither is really critical to replace, as they have simple roles.
I will probably tinker with both designs anyhow.

I also could use a new Minesweeper design, but I have 90 dedicated minesweepers and ~133 others fitted for the ability so it's not critical. However, in 2 years I will have a new Mine tech, so they should wait.

Otherwise everything is 1931 or later designs, so after the introduction of the 1928 artillery designs, new AA, and DP mounts.

Current Naval Classes
1932.5 Arwand "Valiant" Class , Battleships
1935.5 Armored Cruiser A - Zemaka III ACs
1933 Baskuc, Armored Strike Carrier
1933 Wasendag Kaman, Strike Carrier
1934 Manzikert ,Cruiser
1934 Bahkiarti, Cruiser
1935 Kastar, Destroyer Leader
1932.5 Sher, Corvette
1932.5 Robah, Fleet Destroyer
1935 Yoz, Coastal Destroyer
1932.5 MTB-J
1931 Hukar, Gunboat
1926 Motor Gunboat – I, River Gunboat
1931 Sturgeon, Coastal Patrol Cutter II
1932 Xwarg, Fast Minelayer
1933 SS500 1930

Auxiliaries
1932.5 Hamberkastig, Fleet Supply Vessel
1934 Royn, Fleet Oiler
1935 Patrol Sloop – III
1922 Deniz Ghoorbagheh, Light Tender
1934.5 Barge, Light Tender

On carriers
First I went with experimental carriers, which were conversions which have since been scrapped.
Then there was the Fighter Carriers and Flight Deck Cruisers - designed to put up fighters and scouts quickly from many decks. Each fleet and heavy scouting squadron got one or the other.

Then I moved to the mid sized 'Kam Baz' which was meant to launch both fighters and a strike component. As dive bombers were just entering service, these focused on the older main threat - torpedo bombers, with walls of QF AA guns for barrage fire.

Somewhere in all this I expect the Parthians have done their version of the USN's wargames, practicing what one could do with these vessels. I also expect that in scrapping the old ships, some testing may have been done, say on fire suppression.

With that foundation of dispersed fighter launching platforms in service, the decision was made to field larger airgroups with a sufficient strike component as to be able to overwhelm small combatants, or drive through and damage (hopefully below water) a larger combatant. Once slowed, they can be caught and killed by the Parthian line.

The 1935.5 completion of the 'Burning Bow' strike carrier in addition to the completion of the 1938 Aircraft tech means both are brand new during the carrier's shake down cruise. The largest airgroup Parthia has fielded with a mixture of monoplanes and biplanes. Further, the two Basuk class armored strike carriers are completing and will be shaking down in 1936.5.

So I do not think it reasonable for Parthia to immediately start building a new carrier or flight deck cruiser. They would want to take a good look at what they have. So I should wait for 1937 before laying down more carriers.

Kaiser Kirk · December 12, 2024, 10:28:50 PM

The 1926 river gunboat design is a decade old.

At 60 tons it is not a critical warship, I build it mainly for storyline purposes.
Expecting that most villages will be by rivers and fishing harbors, having
a mobile fortress seemed wise.

So the gunboat is meant to operate in coastal and riverine waters, with a 1.25m draft it could
go about anywhere. That allows it to support officers or even marines if there are smugglers to rebels. Regular troops could be encountered in such places as the Orinoco river vs. the Mayans, or the Sumatran coast vs. the Japanese, the Zambezi delta vs. the Byzantine.

The Soviets felt a 75mm was ineffective against midsized log barricades troops could make, but a 100mm could destroy them. So the gunboat mounts a 90L50 for direct fire able to shatter such breastworks and bunkers. The 118mm howitzer allows for fire support beyond the direct riverside. The 15mm MGs allow heavy machine gun fire to suppress defenders. The 23mm gives some AA capacity.

The entire upper surface of the hull is armored, as are the gun faces. The armor is only 20mm, but for this period that is plenty, and even if a foe had a period ATG, the ship would absorb damage much better than a tank would, while be able to blanket the ATG position with return fire.

Unlike the 60ton Series I, the series II dispenses with coal in favor of diesel. I think Parthian basing is sufficiently improved that storage facilities can handle the additional need.

I do wonder if I should scrape up ton more for an Electric battery so that the ship can finish
it's approach silently. Edit - did that, thinned the side shields on the 90mm and 118 from 15 to 12mm. Still plenty bulletproof.

QuoteMGB-2, Pathian Motor Gun Boat II laid down 1936

Displacement:
   70 t light; 84 t standard; 86 t normal; 87 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (64.34 ft / 62.34 ft) x 15.58 ft x (4.76 / 4.81 ft)
   (19.61 m / 19.00 m) x 4.75 m x (1.45 / 1.47 m)

Armament:
1 - 3.54" / 90.0 mm 50.0 cal gun - 24.25lbs / 11.00kg shells, 190 per gun
     Quick firing gun in deck mount, 1926 Model
     1 x Single mount on centreline, forward deck centre
1 - 4.65" / 118 mm 21.0 cal gun - 55.12lbs / 25.00kg shells, 190 per gun
     Quick firing gun in deck mount, 1926 Model
     1 x Single mount on centreline, aft deck centre
4 - 0.91" / 23.0 mm 90.0 cal guns - 0.43lbs / 0.20kg shells, 4,000 per gun
     Anti-air guns in deck mounts, 1936 Model
     2 x Twin mounts on centreline ends, evenly spread
      2 raised mounts
8 - 0.59" / 15.0 mm 70.0 cal guns - 0.00lbs / 0.00kg shells, 5,000 per gun
     Machine guns in deck mounts, 1922 Model
     4 x Quintuple mounts on side ends, evenly spread
Weight of broadside 81 lbs / 37 kg

Armour:
- Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   0.79" / 20 mm     40.52 ft / 12.35 m   9.19 ft / 2.80 m
   Ends:   Unarmoured
     Main Belt covers 100 % of normal length

- Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   0.98" / 25 mm   0.47" / 12 mm      0.31" / 8 mm
   2nd:   0.98" / 25 mm   0.47" / 12 mm      0.31" / 8 mm
   3rd:   0.31" / 8 mm     -           -
   4th:   0.31" / 8 mm     -           -

- Armoured deck - single deck:
   For and Aft decks: 0.39" / 10 mm
   Forecastle: 0.39" / 10 mm Quarter deck: 0.39" / 10 mm

- Conning towers: Forward 0.98" / 25 mm, Aft 0.00" / 0 mm

Machinery:
   Diesel Internal combustion generators,
   Electric motors, 2 shafts, 194 shp / 145 Kw = 11.00 kts
   Range 500nm at 8.00 kts
   Bunker at max displacement = 3 tons

Complement:
   13 - 18

Cost:
   £0.033 million / $0.130 million

Distribution of weights at normal displacement:
   Armament: 10 tons, 11.4 %
     - Guns: 10 tons, 11.4 %
   Armour: 29 tons, 34.1 %
     - Belts: 14 tons, 16.4 %
     - Armament: 9 tons, 10.8 %
     - Armour Deck: 5 tons, 6.4 %
     - Conning Tower: 0 tons, 0.5 %
   Machinery: 5 tons, 6.4 %
   Hull, fittings & equipment: 22 tons, 25.4 %
   Fuel, ammunition & stores: 15 tons, 17.9 %
   Miscellaneous weights: 4 tons, 4.8 %
     - Hull below water: 2 tons
     - Hull above water: 0 tons
     - Above deck: 2 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     160 lbs / 72 Kg = 7.2 x 3.5 " / 90 mm shells or 0.3 torpedoes
   Stability (Unstable if below 1.00): 1.36
   Metacentric height 0.5 ft / 0.2 m
   Roll period: 9.0 seconds
   Steadiness   - As gun platform (Average = 50 %): 75 %
         - Recoil effect (Restricted arc if above 1.00): 1.09
   Seaboat quality (Average = 1.00): 1.60

Hull form characteristics:
   Hull has a flush deck,
     a ram bow and a cruiser stern
   Block coefficient (normal/deep): 0.650 / 0.651
   Length to Beam Ratio: 4.00 : 1
   'Natural speed' for length: 7.90 kts
   Power going to wave formation at top speed: 72 %
   Trim (Max stability = 0, Max steadiness = 100): 47
   Bow angle (Positive = bow angles forward): 13.00 degrees
   Stern overhang: -3.28 ft / -1.00 m
   Freeboard (% = length of deck as a percentage of waterline length):
            Fore end,    Aft end
     - Forecastle:   20.00 %, 8.69 ft / 2.65 m, 7.55 ft / 2.30 m
     - Forward deck:   30.00 %, 7.55 ft / 2.30 m, 7.55 ft / 2.30 m
     - Aft deck:   35.00 %, 7.55 ft / 2.30 m, 7.55 ft / 2.30 m
     - Quarter deck:   15.00 %, 7.55 ft / 2.30 m, 7.55 ft / 2.30 m
     - Average freeboard:      7.64 ft / 2.33 m

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 67.9 %
      - Above water (accommodation/working, high = better): 82.3 %
   Waterplane Area: 744 Square feet or 69 Square metres
   Displacement factor (Displacement / loading): 119 %
   Structure weight / hull surface area: 19 lbs/sq ft or 94 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.54
      - Longitudinal: 16.85
      - Overall: 0.76
   Caution: Hull subject to strain in open-sea
   Excellent machinery, storage, compartmentation space
   Cramped accommodation and workspace room
   Ship has slow, easy roll, a good, steady gun platform
   Excellent seaboat, comfortable, can fire her guns in the heaviest weather

Warning: Beam between bulkheads too wide

Intended as a Coastal/ Riverine gunboat successor to the MGB-I class.
The draft is increased from 1.25 to 1.45m
Armor is increased from 15mm to 20-25mm.

Armor :
Main belt is +2.3 to - 0.50

The Fore / Quarter deck are protective decks
while the citadel has the armor deck capping the belt.

Engineering :
8knots cruise ensures that even fast river currents can be easily over come.
This only takes 35shp.
10 knots is 88shp, or 250%.

Oil sprayed coal is relied on, as wood can be used in a pinch.

To allow maximum manuevers with differential propellors,
turbogenerators are fitted.

Reserve : 0t

AD
1t- FC
1tt - Night Fighting
0t - SR Radio

OD

HAW
0.1t - CO2 Compressor AC

HBW
2.5t - Diesel-Electric Turbogenerator
1t - Batteries for silent running.

Kaiser Kirk · December 12, 2024, 11:10:28 PM

I was not able to find the tonnage to lay down the new Maritime Patrol Frigates.
The three candidates were 4300, 5300 and 6000 tons.
The 4300 and 5300 tonners seemed the best.

They are meant for independent operations around the world, so keeping within a common merchant dock size of ~141m seems wise.

They are not designed to normally stand in line of battle, but if fleet losses are high, could be drawn in.

The new 165L47 fires a heavy shell, giving the ship substantial capability against most cruisers.
The armor is a little thin, but gives the ship immunity to longer ranged cruiser fire.

Anyhow, the 1936 versions...which are very similar to the 1935...need posting.

I think the 5330 ton version is sufficiently more capable that I prefer it,
but for economy over a number of hulls, the 4300 may be better.

Quote4300 ton version

Atossa, Parthian Maritime Patrol Frigate laid down 1936

Displacement:
4,500 t light; 4,825 t standard; 5,595 t normal; 6,211 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
(462.30 ft / 452.76 ft) x 49.21 ft x (15.42 / 16.75 ft)
(140.91 m / 138.00 m) x 15.00 m x (4.70 / 5.10 m)

Armament:
4 - 6.50" / 165 mm 47.0 cal guns - 176.37lbs / 80.00kg shells, 188 per gun
Quick firing guns in deck and hoist mounts, 1931 Model
4 x Single mounts on centreline ends, evenly spread
2 raised mounts - superfiring
8 - 3.54" / 90.0 mm 54.0 cal guns - 24.25lbs / 11.00kg shells, 600 per gun
Dual purpose guns in deck and hoist mounts, 1939 Model
4 x 2-gun mounts on side ends, evenly spread
24 - 1.46" / 37.0 mm 70.0 cal guns - 1.72lbs / 0.78kg shells, 2,600 per gun
Anti-air guns in deck and hoist mounts, 1929 Model
4 x 2 row quad mounts on side ends, evenly spread
4 raised mounts
2 x 2 row quad mounts on centreline ends, evenly spread
2 double raised mounts
16 - 0.91" / 23.0 mm 90.0 cal guns - 0.43lbs / 0.20kg shells, 4,000 per gun
Anti-air guns in deck mounts, 1929 Model
8 x Twin mounts on sides, evenly spread
8 double raised mounts
Weight of broadside 948 lbs / 430 kg

Armour:
- Belts: Width (max) Length (avg) Height (avg)
Main: 2.95" / 75 mm 298.82 ft / 91.08 m 11.91 ft / 3.63 m
Ends: Unarmoured
Main Belt covers 102 % of normal length
Main Belt inclined -15.00 degrees (positive = in)

- Hull void:
0.00" / 0 mm 0.00 ft / 0.00 m 0.00 ft / 0.00 m

- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 3.54" / 90 mm 1.18" / 30 mm 2.95" / 75 mm
2nd: 0.98" / 25 mm 0.98" / 25 mm 0.98" / 25 mm
3rd: 0.79" / 20 mm 0.31" / 8 mm 0.31" / 8 mm
4th: 0.31" / 8 mm - -

- Armoured deck - single deck:
For and Aft decks: 1.54" / 39 mm
Forecastle: 1.38" / 35 mm Quarter deck: 1.38" / 35 mm

- Conning towers: Forward 3.94" / 100 mm, Aft 1.38" / 35 mm

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 3 shafts, 49,219 shp / 36,718 Kw = 30.00 kts
Range 10,100nm at 14.00 kts
Bunker at max displacement = 1,386 tons

Complement:
323 - 420

Cost:
£2.317 million / $9.269 million

Distribution of weights at normal displacement:
Armament: 255 tons, 4.6 %
- Guns: 255 tons, 4.6 %
Armour: 1,024 tons, 18.3 %
- Belts: 437 tons, 7.8 %
- Armament: 94 tons, 1.7 %
- Armour Deck: 458 tons, 8.2 %
- Conning Towers: 36 tons, 0.6 %
Machinery: 1,381 tons, 24.7 %
Hull, fittings & equipment: 1,568 tons, 28.0 %
Fuel, ammunition & stores: 1,095 tons, 19.6 %
Miscellaneous weights: 273 tons, 4.9 %
- Hull below water: 23 tons
- Hull void weights: 60 tons
- Hull above water: 52 tons
- On freeboard deck: 47 tons
- Above deck: 91 tons

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
5,731 lbs / 2,600 Kg = 41.8 x 6.5 " / 165 mm shells or 1.1 torpedoes
Stability (Unstable if below 1.00): 1.11
Metacentric height 2.1 ft / 0.6 m
Roll period: 14.2 seconds
Steadiness - As gun platform (Average = 50 %): 70 %
- Recoil effect (Restricted arc if above 1.00): 0.65
Seaboat quality (Average = 1.00): 1.20

Hull form characteristics:
Hull has a flush deck,
a ram bow and small transom stern
Block coefficient (normal/deep): 0.570 / 0.583
Length to Beam Ratio: 9.20 : 1
'Natural speed' for length: 22.81 kts
Power going to wave formation at top speed: 62 %
Trim (Max stability = 0, Max steadiness = 100): 58
Bow angle (Positive = bow angles forward): 22.00 degrees
Stern overhang: -3.28 ft / -1.00 m
Freeboard (% = length of deck as a percentage of waterline length):
Fore end, Aft end
- Forecastle: 20.00 %, 23.62 ft / 7.20 m, 21.16 ft / 6.45 m
- Forward deck: 32.50 %, 21.16 ft / 6.45 m, 18.70 ft / 5.70 m
- Aft deck: 33.50 %, 18.70 ft / 5.70 m, 17.72 ft / 5.40 m
- Quarter deck: 14.00 %, 17.72 ft / 5.40 m, 17.72 ft / 5.40 m
- Average freeboard: 19.49 ft / 5.94 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 99.2 %
- Above water (accommodation/working, high = better): 182.5 %
Waterplane Area: 16,239 Square feet or 1,509 Square metres
Displacement factor (Displacement / loading): 114 %
Structure weight / hull surface area: 62 lbs/sq ft or 304 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.68
- Longitudinal: 1.73
- Overall: 0.75
Caution: Hull subject to strain in open-sea
Adequate machinery, storage, compartmentation space
Excellent accommodation and workspace room
Ship has slow, easy roll, a good, steady gun platform

Protection
Armored Belt and Protective Deck
Magazine Box.

Horizontal Waterline Protection :
(Belt + ((PD+Box)*1.5/2)
Magazine : 128mm
Machinery : 101mm

Vertical Protection :
Magazine : 70mm
Machinery : 35mm

Belt
+2m to -1.5m
Inclined 15 degrees
3.5 cos (15) = 3.623 = 3.63

Belt Rises to +2m, or 1.5m above slopes of protective deck to guard against shells diving over.
Belt descend -1.5m below waterline

Deck
35mm Protective Deck full length
35mm magazine box - Sides and Roof thicken Protective deck.

417t - Deck
40t - Box
---
457t - needed
457t - paid

Misc
Resv : 45t

AD :
26t - Fire Control 1930
25t - LR Radio
0t - SR Radio
10t - RDF / Jammer
25t- Hulesmeyer Prox detector.
5t - Night fighting gear

OD:
5t - Paravanes
12t - 2TT3 18"
25t - (Ftr) Scout Floatplane
5t - Catapult

HAW:
5t - CO2 compressor AC
5t - Extra Fire Ext

10t - Brig
32t - Marine Boarding Teams (8)

HBW:
5t - Extra Pumps.
15t - Hydrophones
3t - DC for Scoutplanes

Decks

+5.40 Weather Deck
+2.95 Battery Deck
+2.0 Top Main Belt
+0.50 Main Protective Deck
-1.50 Bottom Main Belt
-1.95 1st Platform Deck, lower edge protective deck
-4.37 Engineering
-4.70 Keel.

Quote5300 ton version.

Boran, Parthian Maritime Patrol Frigate laid down 1936

Displacement:
5,330 t light; 5,708 t standard; 6,555 t normal; 7,233 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
(520.92 ft / 515.09 ft) x 52.49 ft x (15.29 / 16.51 ft)
(158.78 m / 157.00 m) x 16.00 m x (4.66 / 5.03 m)

Armament:
6 - 6.50" / 165 mm 47.0 cal guns - 176.37lbs / 80.00kg shells, 200 per gun
Quick firing guns in deck and hoist mounts, 1936 Model
3 x 2-gun mounts on centreline ends, majority forward
2 raised mounts - superfiring
8 - 3.54" / 90.0 mm 54.0 cal guns - 24.25lbs / 11.00kg shells, 400 per gun
Dual purpose guns in deck and hoist mounts, 1936 Model
4 x 2-gun mounts on sides, evenly spread
16 - 1.46" / 37.0 mm 70.0 cal guns - 1.72lbs / 0.78kg shells, 3,200 per gun
Anti-air guns in deck mounts, 1936 Model
4 x 4 row quad mounts on sides, evenly spread
4 raised mounts
32 - 0.91" / 23.0 mm 90.0 cal guns - 0.43lbs / 0.20kg shells, 5,000 per gun
Anti-air guns in deck mounts, 1936 Model
4 x 2 row quad mounts on side ends, evenly spread
8 x Twin mounts on sides, evenly spread
8 double raised mounts
Weight of broadside 1,293 lbs / 587 kg

Armour:
- Belts: Width (max) Length (avg) Height (avg)
Main: 3.94" / 100 mm 334.81 ft / 102.05 m 14.27 ft / 4.35 m
Ends: Unarmoured
Main Belt covers 100 % of normal length
Main Belt inclined -15.00 degrees (positive = in)

- Hull void:
0.00" / 0 mm 0.00 ft / 0.00 m 0.00 ft / 0.00 m

- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 0.98" / 25 mm 0.98" / 25 mm 0.98" / 25 mm
2nd: 0.79" / 20 mm - 0.79" / 20 mm
3rd: 0.79" / 20 mm - -
4th: 0.79" / 20 mm - -

- Armoured deck - single deck:
For and Aft decks: 1.53" / 39 mm
Forecastle: 0.98" / 25 mm Quarter deck: 1.38" / 35 mm

- Conning towers: Forward 1.38" / 35 mm, Aft 0.00" / 0 mm

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 4 shafts, 50,827 shp / 37,917 Kw = 30.00 kts
Range 10,100nm at 14.00 kts
Bunker at max displacement = 1,524 tons

Complement:
363 - 473

Cost:
£2.629 million / $10.517 million

Distribution of weights at normal displacement:
Armament: 323 tons, 4.9 %
- Guns: 323 tons, 4.9 %
Armour: 1,371 tons, 20.9 %
- Belts: 777 tons, 11.9 %
- Armament: 52 tons, 0.8 %
- Armour Deck: 532 tons, 8.1 %
- Conning Tower: 10 tons, 0.2 %
Machinery: 1,426 tons, 21.8 %
Hull, fittings & equipment: 2,006 tons, 30.6 %
Fuel, ammunition & stores: 1,226 tons, 18.7 %
Miscellaneous weights: 203 tons, 3.1 %
- Hull below water: 23 tons
- Hull void weights: 40 tons
- Hull above water: 20 tons
- On freeboard deck: 61 tons
- Above deck: 59 tons

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
8,055 lbs / 3,654 Kg = 58.8 x 6.5 " / 165 mm shells or 1.4 torpedoes
Stability (Unstable if below 1.00): 1.18
Metacentric height 2.6 ft / 0.8 m
Roll period: 13.7 seconds
Steadiness - As gun platform (Average = 50 %): 75 %
- Recoil effect (Restricted arc if above 1.00): 0.72
Seaboat quality (Average = 1.00): 1.50

Hull form characteristics:
Hull has a flush deck,
a ram bow and small transom stern
Block coefficient (normal/deep): 0.555 / 0.567
Length to Beam Ratio: 9.81 : 1
'Natural speed' for length: 24.29 kts
Power going to wave formation at top speed: 57 %
Trim (Max stability = 0, Max steadiness = 100): 50
Bow angle (Positive = bow angles forward): 13.00 degrees
Stern overhang: 0.00 ft / 0.00 m
Freeboard (% = length of deck as a percentage of waterline length):
Fore end, Aft end
- Forecastle: 20.00 %, 25.26 ft / 7.70 m, 22.80 ft / 6.95 m
- Forward deck: 30.00 %, 22.80 ft / 6.95 m, 20.34 ft / 6.20 m
- Aft deck: 35.00 %, 20.34 ft / 6.20 m, 19.03 ft / 5.80 m
- Quarter deck: 15.00 %, 19.03 ft / 5.80 m, 19.03 ft / 5.80 m
- Average freeboard: 20.97 ft / 6.39 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 90.2 %
- Above water (accommodation/working, high = better): 209.5 %
Waterplane Area: 19,428 Square feet or 1,805 Square metres
Displacement factor (Displacement / loading): 119 %
Structure weight / hull surface area: 67 lbs/sq ft or 326 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.68
- Longitudinal: 1.65
- Overall: 0.75
Caution: Hull subject to strain in open-sea
Adequate machinery, storage, compartmentation space
Excellent accommodation and workspace room
Ship has slow, easy roll, a good, steady gun platform
Good seaboat, rides out heavy weather easily

Designed as a new class of Maritime Patrol Frigate
for solo deep ocean patrols and showing the flag worldwide.

'X' mount is raised to give clear arcs over the aircraft on the fantail, ala Littorio.

Protection

Armored Belt, armored Deck, and magazine box.
Magazine Box is abuts belt and deck, where plates are
thickened to 135mm and 70mm.

Horizontal Protection @ Waterline
Magazines : 135mm + slope
Machinery : 100mm + slope

Vertical Protection
Magazines : 70mm
Machinery : 35mm

Belt : 2.7 to -1.5m
Outsloped 15 degrees
4.2/cos(15) = 4.3481599 = 4.35

487t Deck 25/35/35
45t Magazine Box : 35mm
----
532 needed
532 modeled

Miscellaneous Weight
Reserve
55t

AD
33t - FC 1930
25t - LR Radio
0t - SR Radio
25t - Hulesmeyer
6t - Night Fighting Gear

OD
5t - Paravanes
26t - Power assist main battery
25t - (Ftr) Scout Floatplane on stern
5t - Catapult

HAW
5t - CO2 compressor AC
5t - Hanger
10t - Brig

HBW
5t - Extra pumps
15t - Ench Hydrophones
3t - DC for Floatplanes to drop

6.20 to 5.80 Weather Deck
2.7 Battery Deck - Top Main Belt, Armored Deck.
0.2 Main Deck
-1.5 Bottom Main Belt
- 2.3m 1st Platform deck
- 4.15 Engineering
- 4.66 Keel

Kaiser Kirk · December 12, 2024, 11:52:38 PM

Likely last and possibly least.

The 1922 "Sea Frog" Deniz Ghoorbagheh, updated to 1936.
The difference in fuel and engine tonnage was decent, and allowed the weaponry to be upgraded to the current generation of AA.

Looking at the design, I really should reassign these from the Coast Guard squadrons to the MTB squadrons as originally intended. The seaplanes were to scout so the MTBs had solid targets to sortie against. Peacetime working with Coast Guards they provide that ability vs. smugglers, pirates and for locating ships in general.

QuoteDeniz Ghoorbagheh, Parthian Light Tender laid down 1936

Displacement:
   2,800 t light; 2,923 t standard; 2,993 t normal; 3,048 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (260.00 ft / 255.91 ft) x 63.98 ft x (9.84 / 10.00 ft)
   (79.25 m / 78.00 m) x 19.50 m x (3.00 / 3.05 m)

Armament:
8 - 3.54" / 90.0 mm 54.0 cal guns - 24.25lbs / 11.00kg shells, 320 per gun
     Dual purpose guns in casemate mounts, 1931 Model
     8 x Single mounts on sides, evenly spread
8 - 1.46" / 37.0 mm 70.0 cal guns - 1.73lbs / 0.79kg shells, 3,000 per gun
     Breech loading guns in deck mounts, 1929 Model
     2 x 2-gun mounts on sides amidships
      2 raised mounts
8 - 0.91" / 23.0 mm 90.0 cal guns - 0.43lbs / 0.20kg shells, 3,000 per gun
     Breech loading guns in deck mounts, 1929 Model
     4 x Twin mounts on side ends, evenly spread
      4 double raised mounts
Weight of broadside 211 lbs / 96 kg

Machinery:
   Oil fired boilers, steam turbines,
   Geared drive, 2 shafts, 1,479 shp / 1,103 Kw = 12.00 kts
   Range 3,700nm at 8.00 kts
   Bunker at max displacement = 125 tons

Complement:
   201 - 262

Cost:
   £0.618 million / $2.472 million

Distribution of weights at normal displacement:
   Armament: 52 tons, 1.7 %
     - Guns: 52 tons, 1.7 %
   Machinery: 42 tons, 1.4 %
   Hull, fittings & equipment: 981 tons, 32.8 %
   Fuel, ammunition & stores: 192 tons, 6.4 %
   Miscellaneous weights: 1,726 tons, 57.7 %
     - Hull below water: 715 tons
     - Hull void weights: 24 tons
     - Hull above water: 688 tons
     - On freeboard deck: 230 tons
     - Above deck: 69 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     9,709 lbs / 4,404 Kg = 436.5 x 3.5 " / 90 mm shells or 2.2 torpedoes
   Stability (Unstable if below 1.00): 1.72
   Metacentric height 6.2 ft / 1.9 m
   Roll period: 10.7 seconds
   Steadiness   - As gun platform (Average = 50 %): 100 %
         - Recoil effect (Restricted arc if above 1.00): 0.03
   Seaboat quality (Average = 1.00): 2.00

Hull form characteristics:
   Hull has rise aft of midbreak, low quarterdeck ,
     a normal bow and a cruiser stern
   Block coefficient (normal/deep): 0.650 / 0.652
   Length to Beam Ratio: 4.00 : 1
   'Natural speed' for length: 16.00 kts
   Power going to wave formation at top speed: 38 %
   Trim (Max stability = 0, Max steadiness = 100): 50
   Bow angle (Positive = bow angles forward): 13.00 degrees
   Stern overhang: 0.00 ft / 0.00 m
   Freeboard (% = length of deck as a percentage of waterline length):
            Fore end,    Aft end
     - Forecastle:   20.00 %, 17.72 ft / 5.40 m, 15.26 ft / 4.65 m
     - Forward deck:   35.00 %, 15.26 ft / 4.65 m, 12.80 ft / 3.90 m
     - Aft deck:   35.00 %, 21.00 ft / 6.40 m, 21.00 ft / 6.40 m
     - Quarter deck:   10.00 %, 4.59 ft / 1.40 m, -1.08 ft / -0.33 m
     - Average freeboard:      15.68 ft / 4.78 m

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 62.3 %
      - Above water (accommodation/working, high = better): 208.1 %
   Waterplane Area: 12,542 Square feet or 1,165 Square metres
   Displacement factor (Displacement / loading): 155 %
   Structure weight / hull surface area: 64 lbs/sq ft or 313 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.88
      - Longitudinal: 2.87
      - Overall: 1.00
   Excellent machinery, storage, compartmentation space
   Excellent accommodation and workspace room
   Ship has slow, easy roll, a good, steady gun platform
   Excellent seaboat, comfortable, can fire her guns in the heaviest weather

Warning: Beam between bulkheads too wide

"Sea Frog" or Deniz Ghoorbagheh.
Light Tender Design.

2.8 + 9 = 11.8 months to build.
0.35 / HY cost.

The Parthians have a number of large support vessels, allowing them to support the majority
of their fleet far far from home.

To support their desire to be able to sustain localized coastal forces they have
been considering light tenders with a shallow draft.

The tenders would need resupply, but trucks -> lighters->tender can provide that,
or coastal vessels can bring it.

The largest vessels expected to need such support would be the 750ton Subs or Torpedo boats, or a squadron of MTBs.

8 x 750 tons = 6000 tons

This would also support a swarm of MTBs, or subs, or a pair of frigates or even most Parthian cruisers.

The stern is sloped to be slightly awash, to allow aircraft or MTBs to be winched on board. A roller path and winch allows them to be brought into the hanger / maintenance bay area.

A lightly built hanger structure fills the aft deck, arched for lighter construction, and so wind
will not push the vessel sideways.

The hanger is 5m tall, spanning from 1.4m to 6.4m.

Armanent : 2624 * 0.02 = 52.48 vs. 45 carried.
Casements on the ships side at weather deck level preserve the interior space.
batteries of 4 light guns bear on either beam, with the hopes of defense against
a maurading solo gunboat or coastal DD.

A pair of 57mm AA is mounted on each side, again aimed at warding off light air attack.

GAST 15mm are mounted for both strafing defense and boarders.

The ultimate defense is few vessels have a 3m draft, and the tender will scuttle somewhere else.

Miscellaneous Weight

Reserve : 24t

AD
6t FC : The vessel needs to be able to ward off a enemy patrol craft, sub or aircraft.
23t : A 30m high cage mast is the lightest spotting top, and gives best sight lines. Tonnage from USS Texas. Also Air Control platform.
25t : LR Radio - Communciations for the lighter vessels
10t : Dedicated SR radio band for Aircraft.

OD :
20t - Plot Room
80t - 4x Scout Floatplanes.
10t - 2x Gunpowder CAT (each beam)
120t - Aft Hanger / On-deck space to work MTBs under cover.
Conceptually, this is, shown by the raised aft deck, while the stern dives down to form the ramp.

HAW :
3t - Compressor CO2 A/C
40t - Additional Berthing
20t - Surgical Wardroom
25t - Additional fire Suppression
600t - Fleet Support

HBW:
240t : Torpedo/ Mine / Depth Charge storage
60t : Ammunition Storage
400t : Fuel Storage Tanks, double wall
15t : Enhanced Hydrophone station.

Decks :
3.9m Weather Deck
1.4m Strength deck, hanger deck
-2.4m Engineering, stores
-2.9m 0.5m double bottom.

Kaiser Kirk · December 13, 2024, 03:50:50 PM

hmm seem to have lost a post.
*sigh*

Kaiser Kirk · December 14, 2024, 01:08:20 PM

The lost post...also known as the forgotten Cruiser.

First, a dirgression on the Parthian 165mm, 215mm and 190mm guns.

165mm
The Bahktiari class was meant to be the replacement for the Royal Nisean Class.
The new 165mm fired almost the same weight (80 vs 85kg) round, with a smaller cross-section for
better penetration at range. Situated in turrets with better firing angles, there should be a better ROF
as well.

So the 12 gun Bahktiari would be larger, faster, better armored improvements on the Royal Niseans.

215mm
The Xiyon Light Armored Cruisers were fitted with a gun that was designed to be a cruiser killer - the 215mm.

Then I wondered, gee can these new cruisers fit this new gun? So I played with the Bahktiari class and managed to shoe-horn in 8 x 215. While not as balanced as the Bahktiari, the long range gun penetration is much better.

190mm
The old Parthian 180mm firing the 85kg shell was meant to be just below the upper limit of what could be hand operated on a sustained basis. The 2-gun mount weights were also within the upper limit, particularly with power assist allocated.

The advent of cruisers with turrets meant those old limits no longer mattered.
The 165mm and 215mm studies had 4-gun turrets far over those weight limits.

Those design studies made me think about Foxy's long ago indication that IJN cruisers would mount their historical 8" guns. So I wondered what bore size would allow an overweight shell in the same weight range as the IJN 8". Much to my surprise that was slightly under 190mm, so I rounded up. Ironically that means the new Parthian gun is nearly the same size as the Byzantine 191mm gun, but firing a better shell that is to heavy for handloading.

The 190L47 firing a 115kg shell would have 821mps - a fast straight shot with good penetration at range.

Then I needed 2 years to research the gun, and forgot about the design I made for it.

So I have 2 versions of that cruiser.

The original design was a 30 knot cruiser, 12 x 190 and quite well armored.
The next variant uses the Manzikert 31 knot hull, again 12x190, but had to slightly shave the armor.
'Slow & steady roll' is sacrificed for stability, as I try to keep 1.10 + .

Kaiser Kirk · December 14, 2024, 01:10:03 PM

The 30-knot version allows fitting a 150mm belt and 55mm deck,
which is backed by a magazine box, giving overall quite good armor.

QuoteDavazdah Rohk, Parthian Cruiser laid down 1936

Displacement:
   10,000 t light; 10,725 t standard; 11,951 t normal; 12,931 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (523.74 ft / 518.37 ft) x 68.90 ft x (24.05 / 25.47 ft)
   (159.64 m / 158.00 m) x 21.00 m x (7.33 / 7.76 m)

Armament:
12 - 7.48" / 190 mm 47.0 cal guns - 253.53lbs / 115.00kg shells, 160 per gun
     Breech loading guns in turret on barbette mounts, 1936 Model
     3 x 4-gun mounts on centreline ends, majority forward
      1 raised mount - superfiring
12 - 4.53" / 115 mm 47.0 cal guns - 55.12lbs / 25.00kg shells, 320 per gun
     Dual purpose guns in deck and hoist mounts, 1936 Model
     4 x 2-gun mounts on side ends, evenly spread
     2 x 2-gun mounts on sides, forward deck aft
      2 double raised mounts
24 - 1.46" / 37.0 mm 70.0 cal guns - 1.72lbs / 0.78kg shells, 3,000 per gun
     Anti-air guns in deck and hoist mounts, 1936 Model
     6 x 2 row quad mounts on sides, evenly spread
      6 raised mounts
24 - 0.91" / 23.0 mm 90.0 cal guns - 0.44lbs / 0.20kg shells, 5,000 per gun
     Anti-air guns in deck mounts, 1936 Model
     12 x Twin mounts on sides, evenly spread
      12 raised mounts
Weight of broadside 3,756 lbs / 1,704 kg

Armour:
- Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   5.91" / 150 mm   336.94 ft / 102.70 m   10.89 ft / 3.32 m
   Ends:   Unarmoured
     Main Belt covers 100 % of normal length
     Main Belt inclined -15.00 degrees (positive = in)

- Hull void:
      0.00" / 0 mm     0.00 ft / 0.00 m   0.00 ft / 0.00 m

- Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   6.50" / 165 mm   1.97" / 50 mm      4.72" / 120 mm
   2nd:   1.57" / 40 mm   1.38" / 35 mm      1.38" / 35 mm
   3rd:   0.31" / 8 mm   0.31" / 8 mm      0.31" / 8 mm
   4th:   0.31" / 8 mm     -           -

- Armoured deck - single deck:
   For and Aft decks: 2.47" / 63 mm
   Forecastle: 1.38" / 35 mm Quarter deck: 2.17" / 55 mm

- Conning towers: Forward 5.91" / 150 mm, Aft 1.38" / 35 mm

Machinery:
   Oil fired boilers, steam turbines,
   Geared drive, 3 shafts, 72,030 shp / 53,735 Kw = 30.00 kts
   Range 10,240nm at 14.00 kts
   Bunker at max displacement = 2,206 tons

Complement:
   570 - 742

Cost:
   £5.050 million / $20.202 million

Distribution of weights at normal displacement:
   Armament: 973 tons, 8.1 %
     - Guns: 973 tons, 8.1 %
   Armour: 2,576 tons, 21.6 %
     - Belts: 918 tons, 7.7 %
     - Armament: 523 tons, 4.4 %
     - Armour Deck: 1,053 tons, 8.8 %
     - Conning Towers: 82 tons, 0.7 %
   Machinery: 2,021 tons, 16.9 %
   Hull, fittings & equipment: 3,809 tons, 31.9 %
   Fuel, ammunition & stores: 1,951 tons, 16.3 %
   Miscellaneous weights: 620 tons, 5.2 %
     - Hull below water: 71 tons
     - Hull void weights: 80 tons
     - Hull above water: 43 tons
     - On freeboard deck: 168 tons
     - Above deck: 258 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     14,830 lbs / 6,727 Kg = 70.9 x 7.5 " / 190 mm shells or 2.1 torpedoes
   Stability (Unstable if below 1.00): 1.10
   Metacentric height 3.4 ft / 1.0 m
   Roll period: 15.6 seconds
   Steadiness   - As gun platform (Average = 50 %): 53 %
         - Recoil effect (Restricted arc if above 1.00): 0.70
   Seaboat quality (Average = 1.00): 1.06

Hull form characteristics:
   Hull has a flush deck,
     a ram bow and small transom stern
   Block coefficient (normal/deep): 0.487 / 0.497
   Length to Beam Ratio: 7.52 : 1
   'Natural speed' for length: 24.79 kts
   Power going to wave formation at top speed: 60 %
   Trim (Max stability = 0, Max steadiness = 100): 50
   Bow angle (Positive = bow angles forward): 12.00 degrees
   Stern overhang: -3.28 ft / -1.00 m
   Freeboard (% = length of deck as a percentage of waterline length):
            Fore end,    Aft end
     - Forecastle:   20.00 %, 25.26 ft / 7.70 m, 22.97 ft / 7.00 m
     - Forward deck:   30.00 %, 22.97 ft / 7.00 m, 20.34 ft / 6.20 m
     - Aft deck:   35.00 %, 20.34 ft / 6.20 m, 20.34 ft / 6.20 m
     - Quarter deck:   15.00 %, 20.34 ft / 6.20 m, 20.34 ft / 6.20 m
     - Average freeboard:      21.44 ft / 6.54 m

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 83.5 %
      - Above water (accommodation/working, high = better): 168.5 %
   Waterplane Area: 24,077 Square feet or 2,237 Square metres
   Displacement factor (Displacement / loading): 116 %
   Structure weight / hull surface area: 116 lbs/sq ft or 566 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.82
      - Longitudinal: 2.07
      - Overall: 0.90
   Caution: Hull subject to strain in open-sea
   Adequate machinery, storage, compartmentation space
   Excellent accommodation and workspace room

Warning: Beam between bulkheads too wide

The Davazdah Rohk or "Twelve Battles" class is to be named after
heroes of twelve legendary duels between Parthians and Turanians.

This trials the possibility of a 190mm designed to fire a maximum weight shell (115kg)
at 821mps. This will require a new 190L47 gun to be developed 1934-1935.

A 3 turret arrangement is used to save length. This allows it to fit in the old 'Cruiser' docks.
The beam is expanded to 22m to 'fit' the 4x7", slightly more than the 3x 8" USS Baltimore

Protection :

Horizontal @ Waterline :
Magazines : 200mm + slope
Machinery : 135mm + slope

Vertical :
Magazines : 120mm
Machinery : 55mm

Belt :
Belt covers from +1.4m to -1.8m and is outsloped 15degrees
3.2/cos(15) = 3.31288 = 3.32

Deck :
A 65mm magazine box is thickens the adjacent belt and deck.
A 55mm armored deck caps the betl at +1.6m.

116t Magazine Box 65mm
970t Armored Deck 35/55/55mm
-----
1086t needed
1086t paid

New Misc Weight after refit :

Reserve - 50t

AD
98t - Fire Control
25t - LR Radio
10t - SR Radio -dedicated AC command center
0t - SR Radio
25t - Searchlight tower (NF)
25t - Hulesmeyer
25t - AS Radar
25t - SS Radar
25t - FC Radar

OD
5t - Paravanes
32t - 2TT4 21" 4t
55t - 2x 20+5 - Fighter Float + Gunpwdr CAT on Stern
76t - 10% rotating wt Power Assist for 180L47

HAW
10t - Hanger in Stern.
8t - CO2 Compresser A/C
25t - Enhanced Fire Ext.

HBW
15t - Enhanced Hydrophones
25t - Extra Pumps.
31t - 1000kw Diesel Generators.

Decks
+6.2 Forecastle Deck
+3.8 Weather Deck
+1.4 Battery Deck Top belt, Armored Deck
-1.10 Deck
-1.8 Bottom main belt
-3.60
-5.80 Engineering
-6.9 Keel, double bottom

Kaiser Kirk · December 14, 2024, 01:13:36 PM

The 31 knot version has armor slightly worse than the Manzikert class,
but more or less substitutes 8x215 for 12x190

In January I will have to examine folks most recent cruisers and ACs/BCs again,
I think the 31knots is probably worthwhile compared to the faster ACs/BCs of some nations Parthia views as potential opposing forces. I really like the armor, but being easily chased down by a much larger vessel could be an issue.

QuoteDavazdah Rohk, Parthia Cruiser laid down 1936

Displacement:
   10,010 t light; 10,714 t standard; 12,074 t normal; 13,163 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (545.40 ft / 538.06 ft) x 72.18 ft x (21.85 / 23.29 ft)
   (166.24 m / 164.00 m) x 22.00 m x (6.66 / 7.10 m)

Armament:
12 - 7.48" / 190 mm 47.0 cal guns - 253.53lbs / 115.00kg shells, 160 per gun
     Quick firing guns in turret on barbette mounts, 1935 Model
     3 x 4-gun mounts on centreline ends, majority forward
      1 raised mount - superfiring
12 - 4.53" / 115 mm 47.0 cal guns - 55.12lbs / 25.00kg shells, 358 per gun
     Dual purpose guns in deck and hoist mounts, 1931 Model
     4 x 2-gun mounts on side ends, evenly spread
     2 x 2-gun mounts on centreline ends, evenly spread
      2 double raised mounts
16 - 1.46" / 37.0 mm 70.0 cal guns - 1.72lbs / 0.78kg shells, 3,000 per gun
     Breech loading guns in deck and hoist mounts, 1929 Model
     4 x 2 row quad mounts on side ends, evenly spread
      4 raised mounts
12 - 0.91" / 23.0 mm 90.0 cal guns - 0.44lbs / 0.20kg shells, 5,000 per gun
     Breech loading guns in deck mounts, 1929 Model
     6 x Twin mounts on sides, evenly spread
      6 double raised mounts
Weight of broadside 3,737 lbs / 1,695 kg

Armour:
- Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   4.33" / 110 mm   349.74 ft / 106.60 m   10.20 ft / 3.11 m
   Ends:   Unarmoured
     Main Belt covers 100 % of normal length
     Main Belt inclined -15.00 degrees (positive = in)

- Hull void:
      0.00" / 0 mm     0.00 ft / 0.00 m   0.00 ft / 0.00 m

- Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   6.30" / 160 mm   2.17" / 55 mm      4.33" / 110 mm
   2nd:   1.18" / 30 mm   0.98" / 25 mm      0.98" / 25 mm
   3rd:   0.31" / 8 mm     -           -
   4th:   0.31" / 8 mm     -           -

- Armoured deck - single deck:
   For and Aft decks: 2.23" / 57 mm
   Forecastle: 1.38" / 35 mm Quarter deck: 1.97" / 50 mm

- Conning towers: Forward 5.12" / 130 mm, Aft 0.00" / 0 mm

Machinery:
   Oil fired boilers, steam turbines,
   Geared drive, 4 shafts, 82,239 shp / 61,350 Kw = 31.00 kts
   Range 8,272nm at 16.00 kts
   Bunker at max displacement = 2,449 tons

Complement:
   575 - 748

Cost:
   £5.243 million / $20.972 million

Distribution of weights at normal displacement:
   Armament: 962 tons, 8.0 %
     - Guns: 962 tons, 8.0 %
   Armour: 2,244 tons, 18.6 %
     - Belts: 656 tons, 5.4 %
     - Armament: 480 tons, 4.0 %
     - Armour Deck: 1,049 tons, 8.7 %
     - Conning Tower: 58 tons, 0.5 %
   Machinery: 2,307 tons, 19.1 %
   Hull, fittings & equipment: 4,098 tons, 33.9 %
   Fuel, ammunition & stores: 2,065 tons, 17.1 %
   Miscellaneous weights: 398 tons, 3.3 %
     - Hull below water: 66 tons
     - Hull void weights: 40 tons
     - Hull above water: 30 tons
     - On freeboard deck: 65 tons
     - Above deck: 197 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     15,401 lbs / 6,986 Kg = 73.6 x 7.5 " / 190 mm shells or 2.0 torpedoes
   Stability (Unstable if below 1.00): 1.19
   Metacentric height 4.2 ft / 1.3 m
   Roll period: 14.7 seconds
   Steadiness   - As gun platform (Average = 50 %): 51 %
         - Recoil effect (Restricted arc if above 1.00): 0.55
   Seaboat quality (Average = 1.00): 1.02

Hull form characteristics:
   Hull has a flush deck,
     a ram bow and small transom stern
   Block coefficient (normal/deep): 0.498 / 0.509
   Length to Beam Ratio: 7.45 : 1
   'Natural speed' for length: 25.24 kts
   Power going to wave formation at top speed: 61 %
   Trim (Max stability = 0, Max steadiness = 100): 50
   Bow angle (Positive = bow angles forward): 16.00 degrees
   Stern overhang: 0.00 ft / 0.00 m
   Freeboard (% = length of deck as a percentage of waterline length):
            Fore end,    Aft end
     - Forecastle:   20.00 %, 25.59 ft / 7.80 m, 22.97 ft / 7.00 m
     - Forward deck:   30.00 %, 22.97 ft / 7.00 m, 20.67 ft / 6.30 m
     - Aft deck:   35.00 %, 20.67 ft / 6.30 m, 20.67 ft / 6.30 m
     - Quarter deck:   15.00 %, 20.67 ft / 6.30 m, 20.67 ft / 6.30 m
     - Average freeboard:      21.68 ft / 6.61 m

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 89.6 %
      - Above water (accommodation/working, high = better): 185.7 %
   Waterplane Area: 26,447 Square feet or 2,457 Square metres
   Displacement factor (Displacement / loading): 117 %
   Structure weight / hull surface area: 118 lbs/sq ft or 574 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.83
      - Longitudinal: 1.86
      - Overall: 0.90
   Caution: Hull subject to strain in open-sea
   Adequate machinery, storage, compartmentation space
   Excellent accommodation and workspace room

Warning: Beam between bulkheads too wide

Davazdah Rohk - Twelve Battles.

Armor

Protection

Magazine Box forms thicker Belt/Deck plates

Horizontal @ waterline :
Magazines : 175 + incline
Machinery : 110 + incline

Vertical.
Magazines : 115
Machinery : 50

Belt Armor
110 mm, +65mm abreast magazines
Covers from 1.2m to -1.8m
Outsloped 15 degrees
3.00/cos(15) = 3.1058 = 3.11

Deck armor
50mm citadel + 65mm Magizine Box thickened deck over magazine.
114t 65mm magazine box
945t 35/50/50mm deck
------
1049t needeed

1049t paid

Misc

Reserve
70t

AD
97t - FC 1930
25t - LR radio
0t - SR Radio
25t - Hulesmeyer
25t - Air Search Radar
25t - Searchlight Tower (NF)

OD
5t paravanes
50t 2x floatplanes ( 2 scout typically)
10t - 2x Catapults

HAW
20t - hanger in stern
10t - CO2 Compressor AC

HBW
10t - Ex Fire Ext
10t - Ex Pumps
15t - Hydrophones
31t - Auxiliary Diesel generator 1000kw
46nm of fuel is Diesel

Decks
+6.30 Weather Deck
+3.70 Battery Deck
+1.20 Armor Deck, main deck
-1.8 bottom main belt
-1.30 1st Platform Deck
-4.80 Engineering
-5.81 Double Bottom
-6.66 Keel

Kaiser Kirk · December 18, 2024, 10:46:36 AM

Reading The Shattered Sword about Midway from the Japanese perspective, I've realized that 2 ship types may be useful.

The first would be a specialty 'Plane Guard' destroyer type- or even small cruiser. Plane guard ships were assigned to flight ops apparently as early as 1910 - common sense I guess to put a ship where it can pick up a ditched pilot.

Perhaps a Xwarg style fast minelayer with the aft minedeck stripped and a floatplane put there.
However, I know lower L:B helps turn radius, so a dedicated 7:1 Destroyer/cruiser design might be nice.

The other is the CLAA concept, but with a specific tactical role as well.
We all get that a torpedo bomber would want to launch from ahead and abreast of the vessel.
I think we all are aware that two elements launch torpedoes from abreast and ahead are best, as turnign to comb the tracks of one set will put you abreast of the second.
I was aware , but this drove home, just how close to the ship they would launch.

Divebombers of course prefer to go down the centerline of ships if possible, and I think it's notable that of the 3 that surprised and attacked Kaga from the beam, one landed on, and two missed.

As we all know, the vertical bombing proved worthless.
As a side note, what happened in the Mayan war was that vertical bombing failed utterly, leading to axial low altitude bombing of Foxy's old small destroyers. The IJN however had no AA, using their anti-MTB rotary 'hotchkiss' style guns for it. So the Mayans kept trying and over the course of months started figuring out how to land some light hits. They did critical one, but generally just wrecked upperworks over the course of the campaign.

So the logical defensive formation would have a plane guard destroyer trailing, a vessel dead ahead - both of which could engage and disrupt divebombers trying an axial attack, and then 2 vessels at '10 O'Clock' and '2 O'Clock' set right where a torpedo bomber flight would prefer to be launching from.

Lastly, the formation should have 2 types of evasion.
First a preplanned set of turns & straights planned in peace- for which the surrounding ships would try to keep station- needing a speed advantage, or the capital ship governed-, and second the 'independent evasion' for weapons release time.

Speed is useful here to avoid any hits, which mean torpedo nets - which even vs. aerial torpedoes allow bow/stern hits and are 'leaky' - are not the choice for faster ships.

TacCovert4 · December 18, 2024, 11:48:29 AM

Quote from: Kaiser Kirk on December 18, 2024, 10:46:36 AMReading The Shattered Sword about Midway from the Japanese perspective, I've realized that 2 ship types may be useful.

The first would be a specialty 'Plane Guard' destroyer type- or even small cruiser. Plane guard ships were assigned to flight ops apparently as early as 1910 - common sense I guess to put a ship where it can pick up a ditched pilot.

Perhaps a Xwarg style fast minelayer with the aft minedeck stripped and a floatplane put there.
However, I know lower L:B helps turn radius, so a dedicated 7:1 Destroyer/cruiser design might be nice.

The other is the CLAA concept, but with a specific tactical role as well.
We all get that a torpedo bomber would want to launch from ahead and abreast of the vessel.
I think we all are aware that two elements launch torpedoes from abreast and ahead are best, as turnign to comb the tracks of one set will put you abreast of the second.
I was aware , but this drove home, just how close to the ship they would launch.

Divebombers of course prefer to go down the centerline of ships if possible, and I think it's notable that of the 3 that surprised and attacked Kaga from the beam, one landed on, and two missed.

As we all know, the vertical bombing proved worthless.
As a side note, what happened in the Mayan war was that vertical bombing failed utterly, leading to axial low altitude bombing of Foxy's old small destroyers. The IJN however had no AA, using their anti-MTB rotary 'hotchkiss' style guns for it. So the Mayans kept trying and over the course of months started figuring out how to land some light hits. They did critical one, but generally just wrecked upperworks over the course of the campaign.

So the logical defensive formation would have a plane guard destroyer trailing, a vessel dead ahead - both of which could engage and disrupt divebombers trying an axial attack, and then 2 vessels at '10 O'Clock' and '2 O'Clock' set right where a torpedo bomber flight would prefer to be launching from.

Lastly, the formation should have 2 types of evasion.
First a preplanned set of turns & straights planned in peace- for which the surrounding ships would try to keep station- needing a speed advantage, or the capital ship governed-, and second the 'independent evasion' for weapons release time.

Speed is useful here to avoid any hits, which mean torpedo nets - which even vs. aerial torpedoes allow bow/stern hits and are 'leaky' - are not the choice for faster ships.

Reference the Mayan War, the Hotchkiss' attempts were the inspiration behind the Aztec obsession with RoF that led to the 40mm Rotary, and soon to the 20mm Rotary. While the bombings were seen as ineffective, the air attacks at Martinique were much more effective, and showed the direction things were quickly going......coupled with AA guns being relatively light in tonnage, it makes sense to pack a ton of them onboard.

Jefgte · December 18, 2024, 04:01:23 PM

Byzance also takes air attacks very seriously.

Since 1932, DD and CL are equiped with the excellent T2x114 DP.
These ships equiped with 114 & 102DP are assigned as a priority to the protection of the "big ones".
Since 1928, vast majority of ships received 40mm pompom and 12.7

The number of patrol boats & TGB off the bases continues to increase.

Byzance does not plan to build special AA cruisers.
(no Dido - no Atlanta).

TacCovert4 · December 18, 2024, 09:20:36 PM

I keep fiddling with it, and some of my colonial corvettes have 130s that will be traded for 120s in a future refit. But I'm probably never gonna do a Dido. I expect to keep doing DDs with 3x2x120mm, and putting on the increasingly potent 40mm Gatling, and a likely future 20mm gatling instead of the single and twin 30mm mounts. The Aztec obsession, in the absence (currently) of multi-mount radar-directed fire control is to put 'maximum firepower on a single line of bearing', having a protected mount that's able to draw from a deep magazine to put maximum AA firepower onto a target as each mount is acting somewhat independently.

In the second half of 1936 I'm going to start the 20mm Gatling project (Roleplaying that the 40mm gatling is now finally getting the bugs worked out after several years in service). And a 155mm/55 gun to replace the 180mm in service as a cruiser weapon.

Kaiser Kirk · December 19, 2024, 12:39:26 AM

I think those were reasonable lessons from that conflict.

The IJN had both old 1912 Fire Control and lacked AA, while the Mayans had 1918 and 47mm(?) which I took as early AA - but rather ineffectual.

The vertical bombing had a very small chance, and was basically ineffectual.
The torpedo planes had success, but at a low rate - if the defenders had decent AA, there may have been a different result. But even bow hits proved limiting to the Mayans, and placed a limit on maximum speed and necessitated seeking an anchorage out of search range to shore up bulkheads. Very troublesome for operations.

After the war, you saw the Parthians develop new guns and refitted their fleet with new AA and FC in the late 1920s-early 1930s. Took quite a while.

The 90/120/130 mix, already too many sizes, had a 115 option added to confuse my supply chains.
Still, they all have 'improved' DP mounts.

The 130 is primarily Anti-surface with a DP AA role.
The 115 will eventually replace 120s in service as a DP weapon, while the 90 will continue as primarily for AA use.

The old 57mm was to slow to train and fire, with too small a burst and was phased out.

The 37mm in a quad wirblewind-style mounting was fielded to allow concentrated rapid fire out to a range beyond where the torpedoes would launch - better than combining the fire of separate mounts.
Most of these are rated as 'deck and hoist', and may have thin 6-8mm armor to ensure a sealed feed from the AA magazine, not crew making a chain to deliver clips. Magazine sizes have grown to allow repeat engagements.

The 15mm Gardner & 15mm GAST was upgraded to the 23mm GAST. While I still like the 15mm and it would be a serious threat it is unlikely to get enough rounds on target pre-weapon release.

The 23mm has a great deal more heft and can deliver effective fire further, while still being a relatively low mass weapon. The GAST arrangement allows rapid fire, and while I expect heat would be an issue, there are a number of potential design/practice options that could have been taken to address that.
Plus it's cool looking. Good enough.

But I've also tried top pay attention to firing arc, and forward fire for my DP/AA weapons, at least conceptually. There's a number of designs with a 'C' & 'x' mount double superimposed to allow more end-on fire.

As for AA cruisers, I wasn't planning on it. I had rebuilt ships into the trial CLAAs, but I did not have follow on designs.

I'd toyed with the idea of a Command Cruiser with a heavy AA suite and a flag bridge - not meant for Ship-Ship battles, but to command the fleet and defend itself and others from air attack.

BUT... After my musing about the usefulness of one or two forward vessels to interfere with clean torpedo attack runs, the Parthians will probably field something for that role. I expect likely a destroyer-hull.

Though I may try a broadside cruiser with a large number of casemented & mounted DP guns, much like the Kam Baz Carrier with tiers of DP weapons to allow barrage engagement of torpedo planes.
Just think - fit a row of casements with 10-12 guns per side.
Then go for double casements...for another 10-12.
Then add deck edge mounts like the RN's carriers had for another 10-12.
Then go for a row of superimposed mounts for another 10-12.
And don't forget 4 mounts on centerline for another 8 (twins) to 16 (quads).

....you could have a 64 gun broadside !!
That's a ship of the line !
AA style !!!!

Now add proximity fuses...

Kaiser Kirk · December 20, 2024, 10:59:29 PM

A non-serious look at a Parthian CLAA Cruiser.

The core concept is gun tiers, with 8 gun positions per side per tier.
On an 160m hull, 65% is 104m, which is a gun per 12m.

Then between casements, deck edge mounts, and on deck and above deck mounts, there are 4 tiers
The lowest level, the casements have the deck level at 3m, so the gun bore is ~4 to 4.5m above waterline, allowing use in most sea states. Worse weather is expected to severely limit torpedo attackers.
The upper tiers are mounts, allowing 2 gun set ups.

Designed to maximize broadside fire against torpedo bombers or dive bombers.
37 & 23 : 2 mounts up.
130 Above Deck
_____130 On Deck
|130 Below Deck : 'frying pan' deck edge mounts. Mount, Below deck.
|130 Lower Deck : Casement
|

8.0m- freeboard
5.5m - battery deck floor
3.00m - casement deck floor
0.50m - main deck level

Overall the total number of barrels is ... large.

QuoteRat a tat tat, Parthian Anti-aircraft cruiser laid down 1936

Displacement:
   10,000 t light; 12,890 t standard; 14,394 t normal; 15,597 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (524.93 ft / 518.37 ft) x 62.34 ft x (26.25 / 27.99 ft)
   (160.00 m / 158.00 m) x 19.00 m x (8.00 / 8.53 m)

Armament:
16 - 5.12" / 130 mm 50.0 cal guns - 85.98lbs / 39.00kg shells, 360 per gun
     Dual purpose guns in casemate mounts, 1936 Model
     16 x Single mounts on sides, evenly spread
      16 hull mounts in lower casemates- Limited use in heavy seas
104 - 5.12" / 130 mm 50.0 cal guns - 85.98lbs / 39.00kg shells, 360 per gun
     Dual purpose guns in deck and hoist mounts, 1936 Model
     48 x 2-gun mounts on sides, evenly spread
      16 raised mounts
      16 hull mounts in casemates- Limited use in heavy seas
     4 x 2-gun mounts on centreline ends, evenly spread
      2 raised mounts - superfiring
72 - 1.46" / 37.0 mm 70.0 cal guns - 1.72lbs / 0.78kg shells, 6,000 per gun
     Anti-air guns in deck and hoist mounts, 1936 Model
     18 x 4-gun mounts on centreline ends, evenly spread
      18 double raised mounts
64 - 0.91" / 23.0 mm 90.0 cal guns - 0.44lbs / 0.20kg shells, 8,000 per gun
     Machine guns in deck mounts, 1936 Model
     32 x Twin mounts on centreline, evenly spread
      32 double raised mounts
Weight of broadside 10,470 lbs / 4,749 kg

Armour:
- Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   1.97" / 50 mm   400.92 ft / 122.20 m   9.48 ft / 2.89 m
   Ends:   Unarmoured
     Main Belt covers 119 % of normal length
     Main belt does not fully cover magazines and engineering spaces

- Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   0.31" / 8 mm   0.31" / 8 mm      0.31" / 8 mm
   2nd:   0.31" / 8 mm   0.31" / 8 mm      0.31" / 8 mm
   3rd:   0.31" / 8 mm     -           -
   4th:   0.31" / 8 mm     -           -

- Protected deck - single deck:
   For and Aft decks: 1.38" / 35 mm
   Forecastle: 1.38" / 35 mm Quarter deck: 1.38" / 35 mm

- Conning towers: Forward 1.97" / 50 mm, Aft 0.00" / 0 mm

Machinery:
   Oil fired boilers, steam turbines,
   Geared drive, 4 shafts, 84,728 shp / 63,207 Kw = 30.00 kts
   Range 8,184nm at 16.00 kts
   Bunker at max displacement = 2,707 tons

Complement:
   656 - 854

Cost:
   £8.196 million / $32.782 million

Distribution of weights at normal displacement:
   Armament: 2,676 tons, 18.6 %
     - Guns: 2,676 tons, 18.6 %
   Armour: 1,118 tons, 7.8 %
     - Belts: 306 tons, 2.1 %
     - Armament: 167 tons, 1.2 %
     - Armour Deck: 619 tons, 4.3 %
     - Conning Tower: 25 tons, 0.2 %
   Machinery: 2,377 tons, 16.5 %
   Hull, fittings & equipment: 3,395 tons, 23.6 %
   Fuel, ammunition & stores: 4,394 tons, 30.5 %
   Miscellaneous weights: 434 tons, 3.0 %
     - Hull below water: 41 tons
     - Hull above water: 20 tons
     - On freeboard deck: 5 tons
     - Above deck: 368 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     10,052 lbs / 4,559 Kg = 149.9 x 5.1 " / 130 mm shells or 1.2 torpedoes
   Stability (Unstable if below 1.00): 1.11
   Metacentric height 3.0 ft / 0.9 m
   Roll period: 15.1 seconds
   Steadiness   - As gun platform (Average = 50 %): 50 %
         - Recoil effect (Restricted arc if above 1.00): 2.52
   Seaboat quality (Average = 1.00): 1.37

Hull form characteristics:
   Hull has a flush deck,
     a ram bow and small transom stern
   Block coefficient (normal/deep): 0.594 / 0.603
   Length to Beam Ratio: 8.32 : 1
   'Natural speed' for length: 24.49 kts
   Power going to wave formation at top speed: 62 %
   Trim (Max stability = 0, Max steadiness = 100): 36
   Bow angle (Positive = bow angles forward): 12.00 degrees
   Stern overhang: -6.56 ft / -2.00 m
   Freeboard (% = length of deck as a percentage of waterline length):
            Fore end,    Aft end
     - Forecastle:   20.00 %, 27.56 ft / 8.40 m, 26.25 ft / 8.00 m
     - Forward deck:   30.00 %, 26.25 ft / 8.00 m, 26.25 ft / 8.00 m
     - Aft deck:   35.00 %, 26.25 ft / 8.00 m, 26.25 ft / 8.00 m
     - Quarter deck:   15.00 %, 26.25 ft / 8.00 m, 26.25 ft / 8.00 m
     - Average freeboard:      26.35 ft / 8.03 m

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 123.6 %
      - Above water (accommodation/working, high = better): 183.6 %
   Waterplane Area: 24,095 Square feet or 2,238 Square metres
   Displacement factor (Displacement / loading): 99 %
   Structure weight / hull surface area: 112 lbs/sq ft or 545 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.78
      - Longitudinal: 3.32
      - Overall: 0.90
   Caution: Hull subject to strain in open-sea
   Cramped machinery, storage, compartmentation space
   Excellent accommodation and workspace room
   Good seaboat, rides out heavy weather easily

Warning: Wrong mount for dual purpose gun - Main Battery

8 gun positions on each side at each level.

Designed to maximize broadside fire against torpedo bombers or dive bombers.
37 & 23 : 2 mounts up.
130 Above Deck
_____130 On Deck
|130 Below Deck : 'frying pan' deck edge mounts. Mount, Below deck.
|130 Lower Deck : Casement
|

8.0m- freeboard
5.5m - battery deck floor
3.00m - main deck floor
0.50m -

Misc Weight
Reserve :

AD
268t- Fire Control 1930
25t- Hulesmeyer
25t- Searchlights (NF)
25t - Air Search Radar
25t- LR Radio
0t- SR Radio

OD
5t - Paravanes

HAW

10t - Additional Ventilation
10t - Additional Fire Suppresion.

HBW
10t- Additional Pumps
31t - Auxiliary Diesel Generator

Despite how ridiculous it is, there's a slight temptation to build it.